Method and Apparatus for Condensing Charges of Vapor

ABSTRACT

A method for condensing on a heat buffer body in a condenser condensable components of charges of vapor intermittently released from a process vessel, wherein, while a part of a vapor charge is supplied directly to the heat buffer body for condensation, another part of the vapor charge is first supplied to a vapor buffer space for buffering, and wherein the other part of the vapor charge is supplied to the heat buffer body only after at least partial condensing of the first part of the vapor charge. The invention also concerns an apparatus for condensing on a heat buffer body in a condenser condensable components of charges of vapor intermittently released from a process vessel.

The invention relates to the condensing, on a heat buffer body in a condenser, of condensable components of charges of vapor released periodically, i.e., intermittently, from a process vessel.

An example of a process in which intermittently charges of vapor are released is a steam peeling process, in which intermittently charges of steam are released from the peeling vessel. NL 1 021 988 describes a method and an apparatus for condensing intermittently released vapor charges from a steam peeling process. A vapor charge is periodically supplied to a heat buffer body set up in a housing of a condenser, which heat buffer body is sprayed at the top with a relatively cold coolant. Condensable components of a charge of vapor thereby condense on the heat buffer body. Non-condensable components of a vapor charge leave the housing at the top via a chimney after they have passed via the heat buffer body. Non-condensable components can be formed, for example, by air and/or peeling residues. Condensable components can be formed, for example, by an excess of water molecules.

Advantageous about this method is that it counteracts condensable components of the charge of vapor leaving the condenser. As a result, a malodor in an environment of the condenser can be limited, because product residues that are condensable are in fact condensed on the heat buffer body. In particular, to this end, the temperature of the coolant is chosen sufficiently low, and the magnitude of the heat buffer body sufficiently high, to allow the condensable components of the whole vapor charge to be condensed upon passage of the heat buffer body.

A disadvantage of this method, however, is that the required apparatus is relatively costly, and that the relatively low cooling water temperature limits later possibilities of use thereof.

The object of the invention is to provide a method and an apparatus in which, with preservation of the advantages mentioned, the disadvantages mentioned are counteracted.

To this end, the invention provides a method for condensing on a heat buffer body in a condenser condensable components of charges of vapor intermittently released from a process vessel, wherein, while a part of a vapor charge is supplied directly to the heat buffer body for condensation thereon, another part of the vapor charge is first supplied to a vapor buffer space for volume buffering, and wherein the other part of the vapor charge is supplied to the heat buffer body only after at least partial condensing of the first part of the vapor charge.

By thus buffering a part of the vapor charge, it is possible to supply that part of the charge to the heat buffer body in a delayed manner, so that the period in which the vapor charge is supplied to the heat buffer body can be prolonged. As a consequence, a smaller heat buffer body can be chosen, which lowers the costs of the apparatus. Also, the temperature of the coolant of the heat buffer body can be increased, which augments further possibilities of use of the coolant after it has left the condenser. The coolant can comprise, for example, water, and may possibly consist substantially of water.

An important idea behind the invention is that a part of the vapor charge is first collected in a vapor buffer space before it is supplied to the heat buffer body. Later, the collected vapor is still condensed on the heat buffer body. Preferably, this occurs as a result of a sucking action arising from a volume decrease of condensing vapor already present in the heat buffer body. A time duration of the thermal loading of the heat buffer body by condensation can therefore be greater than a time duration of the release of a single vapor charge from the process vessel.

It is noted that within the context of this application, intermittently) should be understood to mean that a process vessel is periodically opened and that a charge of vapor to be condensed is emitted therefrom, while the opening time of the process vessel during which the charge of vapor is emitted is short in relation to the period in which the vessel is opened. The process period is then in the order of magnitude of a few minutes or tens of seconds, and the opening time is then in the order of magnitude of a few seconds. The process period is, for example, about 30 sec-3 min, while the opening period is, for example, about 1-3 sec.

It is noted furthermore that within this context the heat buffer body is a material buffer, i.e., a body of solid substance which can take up condensation heat from the vapor and which in turn can give off the condensation heat to the coolant. The vapor buffer space is a volume buffer, i.e., a space in which the vapor itself can be taken up and from which the vapor can be given off again. The heat buffer body can be set up in the vapor buffer space, the vapor buffer space then forms, for example, an integral part of a casing surrounding the heat buffer body. However, the heat buffer body can also be set up outside the vapor buffer space, the vapor buffer space is then, for example, in fluid communication with the above-mentioned space within the casing of the heat buffer body, and is surrounded by a separate casing.

The vapor charge preferably involves steam, and the pressure in the condenser and in the vapor buffer space are then substantially atmospheric. This can be achieved in an elegant manner when the vapor buffer space is in open communication with the ambient air. Preferably, the method comprises on the basis of mass density difference in a separation zone keeping substantially separate the other part of the vapor charge of relatively low mass density and ambient air of relatively high mass density. In the separation zone a volume concentration of the ambient air can be approximately equal to a volume concentration of the second vapor mass. Preferably, the method comprises supplying the other part of the vapor charge at least partly from above the separation zone to the heat buffer body. The above-mentioned measures reflect an idea behind the invention which comprises condensing a released vapor charge in two steps, wherein the other, second part of the vapor charge is temporarily stored in a buffer, here the vapor buffer space. This can be carried out in an advantageous manner in that the second part of the vapor charge can remain substantially unmixed with ambient air. The other vapor charge of relatively low mass density can be kept separate from ambient air of relatively high mass density by collecting the other vapor charge above the separation zone with the outside air and supplying same again from this high position, for example by suction, towards the condenser.

Preferably, the method comprises the following steps: —transporting a first part of a vapor charge to the heat buffer body, followed by condensing the first part of the vapor charge on the heat buffer body; —transporting another, second part of the vapor charge to a vapor buffer space bounded by a casing, followed by collecting of the second part of the vapor charge in the vapor buffer space during and possibly after the, at least partial, condensing of the first part of the vapor charge on the heat buffer body.

Collecting (or collection) of the second part of the vapor charge in the vapor buffer space may be interpreted broadly. During collection, the vapor charge can be substantially at rest. Alternatively or additionally, the vapor charge can be in motion during collection. Optionally, collection of the second part of the vapor charge can comprise diverting the second part of the vapor charge. Such diversion can be designed such that the second part of the vapor charge is transported over a longer distance and/or with a lower flow rate to the heat buffer body than the first part of the vapor charge. Preferably, the first part of the vapor charge condenses on the heat buffer body without having been collected in the vapor buffer space.

Preferably, a first path along which the first part of the vapor charge is transported to the heat buffer body to condense thereon is different from a second path along which the second part of the vapor charge is transported to the heat buffer body to condense thereon. The second path runs via the vapor buffer space to the heat buffer body, and optionally via the heat buffer body before the second path reaches the vapor buffer space. The first path preferably runs to the heat buffer body bypassing the vapor buffer space.

Preferably, the method comprises, after supplying the second part of the vapor charge from the vapor buffer space to the heat buffer body, condensing the second part of the vapor charge on the heat buffer body after at least partial condensing of the first part of the vapor charge on the heat buffer body. As a result, a period is prolonged in which the vapor is supplied to the heat buffer body. In this way, temperature fluctuations of the discharged coolant can be reduced. Also, variations in a flow rate of discharged condensation can be reduced.

Preferably, the second part of the vapor charge is supplied downwards from the vapor buffer space to the heat buffer body.

In an embodiment, the method comprises, during collection of the second part of the vapor charge in the vapor buffer space, discharging residual gas from the vapor buffer space via an outlet situated near an underside of the vapor buffer space. Discharge of the residual gas can take place, for example, by displacement by the second part of the vapor charge. As the residual gas generally has a relatively low temperature and relatively high mass density with respect to the second vapor charge, the outlet situated near an underside of the vapor buffer space will generally effect an improved separation with and/or displacement of the residual gas. This can reduce mixing between the second part of the vapor charge and the residual gas.

In an embodiment, the second part of the vapor charge is transported to the vapor buffer space via the heat buffer body. As a result, it can suffice, for example, to use a single conduit for transport of the vapor charge from the process vessel to the condenser, through which both the first part of the vapor charge and the second part of the vapor charge can be transported. In an embodiment, the second part of the vapor charge is transported to the vapor buffer space bypassing the heat buffer body and/or the condenser. This allows a length of the period in which the vapor charge can be supplied to the heat buffer body to be chosen with a greater freedom.

Preferably, the first part of the vapor charge is transported to the heat buffer body through a supply of the condenser. Preferably, the first part of the vapor charge is conducted substantially upwardly through the heat buffer body. This can be achieved, for example, when the supply is connected to the condenser near an underside of the heat buffer body. As a result, when the second part of the vapor charge is transported to the vapor buffer space via the heat buffer body, the second part of the vapor charge can be collected at a location higher than the heat buffer body. This facilitates the downward supply of the second part of the vapor charge from the vapor buffer space to the heat buffer body.

Preferably, the method further comprises discharging the coolant to a process space, which process space is designed for carrying out a heat requiring process. This embodiment can be of high practical importance, and combines well with the possibility offered by the invention of prolonging the period in which the vapor charge is supplied to the heat buffer body and thereby working with a relatively high temperature of the coolant supplied. As the coolant temperature can be relatively high, the coolant can be rendered suitable for one or more of relatively many different heat requiring processes, without necessitating supply of extra energy to the coolant to increase the temperature.

In an embodiment, a frequency of the intermittent release of the vapor charges, an opening time of the process vessel for releasing the vapor charge, a volume of the first and the second part of the vapor charge, a flow rate of the coolant flow, and a heat capacity of the heat buffer body are chosen for controlling the temperature of the coolant in a range of from 70 to 100 degrees Celsius.

In an embodiment, the method comprises peeling tuberous crops, in particular potatoes, in the process vessel by means of a steam peeling process, which steam peeling process comprises intermittently releasing steam charges from the process vessel.

The invention also provides an apparatus for condensing condensable components of charges of vapor intermittently released from a process vessel, comprising a condenser provided with a heat buffer body for condensing thereon the condensable components of the released vapor charges and with a supply for transporting the released vapor charges therethrough from the process vessel to the heat buffer body, characterized in that the apparatus is provided with a vapor buffer space bounded by a casing, which is in fluid communication with the supply and which is designed for, while a part of a released vapor charge is condensing, therein collecting another part of the vapor charge, and which is in fluid communication with the heat buffer body for supplying the other part of the vapor charge to the heat buffer body after the first part of the vapor charge has at least partly condensed thereon.

With the aid of such an apparatus it is possible to supply the intermittently released vapor masses partly with a delay to the heat buffer body. So, a period in which the vapor charge is supplied to the heat buffer body can be prolonged, and a temperature of coolant which is supplied to the heat buffer body can be increased, which augments further possibilities of use of the coolant.

In an embodiment, the vapor buffer space is situated at least partly above the heat buffer body.

Preferably, the casing is provided with an outlet for gas discharge to an environment of the casing.

Preferably, the outlet is placed for, in use, keeping the other part of the vapor charge and ambient air substantially separate, in that, in use, a separation zone between the other part of the vapor charge and the ambient air is situated lower than at least a part of the other part of the vapor charge. This can be achieved, for example, in that the outlet is situated near an underside of the vapor buffer space. The separation zone can be situated, for example, in or near the outlet. Preferably, the outlet is situated lower than an upper side of the heat buffer body. Since residual gas, which can be present in the vapor buffer space, generally has a lower temperature than the second vapor charge, the outlet situated near an underside of the vapor buffer space can effect an improved displacement of the residual gas. Mixing between the second part of the vapor charge and the residual gas can thereby be reduced. This reduced mixing can reduce air being sucked in through the outlet to the heat buffer body as a result of condensation in the heat buffer body.

In an embodiment, the casing is in fluid communication with the supply via the heat buffer body. This allows the second part of the vapor charge to be supplied from the vapor buffer space to the heat buffer body. Preferably, the casing, alternatively or additionally to being in fluid communication via the heat buffer body, is in fluid communication with the supply outside the heat buffer body and/or the condenser. This allows the second part of the vapor charge to be transported to the vapor buffer space bypassing the heat buffer body and/or the condenser. This allows a length of the period in which the vapor charge can be supplied to the heat buffer body to be chosen with a greater freedom.

In an embodiment, the supply is connected to the condenser near an underside of the heat buffer body. As a result, the first part of the vapor charge, and possibly the second part of the vapor charge, can be conducted substantially upwardly through the heat buffer body.

In an embodiment, the apparatus is provided with a coolant supply for cooling the heat buffer body by means of a coolant flow over a surface of the heat buffer body. This can lead to the coolant at least partly preventing dirt, such as peel residues, from accumulating from the vapor charges onto the heat buffer body. Preferably, the discharge is also designed for discharging the coolant.

In an embodiment, the apparatus is provided with a process space, the apparatus being designed for discharging the coolant to the process space for heating the process space. This embodiment combines well with the possibility offered by the invention of prolonging the period in which the vapor charge is supplied to the heat buffer body and thereby working with a relatively high temperature of the coolant supplied. As the coolant temperature can be relatively high, the coolant can be rendered suitable for one or more of relatively many different heat requiring processes, without necessitating supply of extra energy to the coolant to increase the temperature.

In an embodiment, the heat buffer body comprises a package with a plurality of smooth plates which are set up together with mutual interspaces. Preferably, the plates are made substantially of steel.

In an embodiment, the casing comprises a synthetic, in particular a plastic. The casing is made, for example, of the synthetic. With such materials, a relatively good heat insulation of the casing can be achieved. This can at least partly prevent the second part of the steam charge from condensing on the casing during collection.

In an embodiment, the apparatus also comprises a process vessel. Preferably, the process vessel is designed for carrying out a process under pressure, wherein under the influence of the pressure intermittently a vapor charge is released during an opening time of the process vessel, while a heat capacity of the heat buffer body is chosen so small that, in use, supply of the vapor charge to the heat buffer body leads to condensation of only a part, for example, the first part, of the vapor charge during a time interval equal to the opening time.

In an embodiment, a volume of the vapor buffer space is greater, in particular five times greater, more particularly ten times greater, for example, fifteen times greater, than a volume of the process vessel. This allows expansion of the charges of vapor from the process vessel to the vapor buffer space.

In an embodiment, the process vessel is designed for peeling crop products, in particular vegetables and/or fruit, more particularly tuberous crops, for example, potatoes, by means of a steam peeling process which comprises intermittently releasing steam from the process vessel.

Further advantageous embodiments are represented in the subclaims.

The invention will now be illustrated on the basis of a drawing, in which:

FIG. 1 shows a schematic representation of an apparatus for condensing condensable components of charges of vapor in a first embodiment according to the invention;

FIG. 2 shows a cross section of a condenser of the apparatus according to the first embodiment and variants thereof;

FIG. 3 shows a schematic representation of an apparatus for condensing charges of vapor in a second embodiment according to the invention;

FIG. 4 shows a schematic representation of an apparatus in a third embodiment according to the invention; and

FIG. 5 shows a graph in which a weight of steam masses is shown as a function of time.

It is noted that the figures are only schematic representations of non-limiting exemplary embodiments of the invention. In the figures the same or corresponding parts are represented with the same reference numerals.

FIG. 1 shows a schematic representation of an apparatus 2 for condensing condensable components of charges of vapor in a first embodiment according to the invention. The apparatus 2 can be designed, for example, for condensing charges of water vapor, in particular steam, which are intermittently released from a process vessel 3 and which contain condensable and non-condensable components. To this end, the apparatus 2 is provided with a condenser 4. The condenser 4 is provided with a heat buffer body 5 for thereon condensing (the condensable components of) the released charges of vapor. It will be clear that herein ‘condensing the vapor charge’ is generally understood to mean ‘condensing condensable components of the vapor charge’.

The process vessel 3 can be designed, for example, for peeling crop products, in particular vegetables and/or fruit, more particularly tuberous crops, for example, potatoes, by means of a steam peeling process which comprises intermittently releasing steam from the process vessel. The condenser 4 is further provided with a supply 6 for transporting therethrough the released charges of vapor from the process vessel 3 to the heat buffer body 5. The supply 6 can be formed, for example, by means of a conduit. In the figure it is indicated with an arrow that the supply is provided with a valve. The conduit is preferably made of a material that is resistant to pressures of up to at least 16 bar, in particular at least 25 bar, and temperatures of up to at least 200 degrees Celsius, in particular up to at least 225 degrees Celsius. What can be achieved in this manner is that the conduit is resistant to typical pressures and temperatures that can be attained in a steam peeling process. The conduit can contain, for example, a metal, for example, steel.

The apparatus 2 is further provided with a vapor buffer space 8. The vapor buffer space is bounded by a casing 10. The casing preferably contains a synthetic, in particular a plastic. With such materials, a relatively good heat insulation of the casing can be achieved. This can, at least partly, prevent collected vapor from condensing in the vapor buffer space instead of on the heat buffer body.

The supply 6 and the vapor buffer space 8 are in fluid communication with each other, in this example via the heat buffer body 5. In FIG. 1 double-headed arrow 7A indicates the fluid communication between the supply and the vapor buffer space via the heat buffer body. In another embodiment, the apparatus 2 is provided with an additional fluid communication 7B between the supply 6 and the vapor buffer space 8. The vapor buffer space 8 is thus in fluid communication with the supply bypassing the heat buffer body 5 and/or the condenser 4. This allows the vapor charge to be partly transported to the vapor buffer space 8 bypassing the heat buffer body 5 and/or the condenser 4. The vapor buffer space 8 is designed for, while a first part of a released vapor charge is condensing, therein collecting another, second part of the vapor charge. More generally, the second part of the vapor charge can be, for example, at least as great as the first part of the vapor charge.

In the first embodiment, the vapor buffer space 8 is in fluid communication with, and situated at least partly above, the heat buffer body 5. As a result, in use, the second part of the vapor charge can be supplied to the heat buffer body 5. This supply can take place after the first part of the vapor charge has at least partly condensed on the heat buffer body 5. This prolongs a period in which the vapor is supplied to the heat buffer body 5.

In FIG. 1 a first path along which the first part of the vapor charge is transported to the heat buffer body 5 to condense thereon is formed by the supply 6. A second path along which the second part of the vapor charge is transported to the heat buffer body 5 to condense thereon can be formed by the supply 6, the additional fluid communication 7B, and the vapor buffer space 8. Alternatively or additionally, the second path can be formed by the supply 6, the heat buffer body 5, and the vapor buffer space 8. In both examples, the second path runs to the heat buffer body 5 via the vapor buffer space 8. The first path runs to the heat buffer body 5 bypassing the vapor buffer space 8.

The casing 10 can be provided with an outlet 12 for gas discharge to an environment of the casing 10, for example, to outside air. Preferably, the outlet 12 is situated near an underside 13 of the vapor buffer space. As a result, charges of vapor of relatively high temperature and relatively low mass density with respect to the outside air of relatively low temperature and relatively high mass density can be collected in the vapor buffer space 8 relatively well. Further, in this way it is possible to maintain a relatively good separation between the charges of vapor and residual gas (for example, originating from the outside air). Owing to the above-mentioned separation, supply of the residual gas together with the second part of the vapor charge to the heat buffer body 5 is, at least partly, prevented. Also, an adverse influence of the residual gas on condensation processes in the condenser 4 can, at least partly, be limited. Such an adverse influence can be, for example, that the residual gas, like other non-condensable components, in the heat buffer body lowers the condensation rate of vapor by forming a barrier between the vapor and the heat buffer body 5. Thus, it will be clear that in this example the outlet 12 is arranged for, in use, keeping the second part of the vapor charge and ambient air, in particular the outside air, substantially separate, in that, in use, a separation zone 15 between the second part of the vapor charge and the ambient air can be situated lower than the second part of the vapor charge. In the separation zone a volume concentration of the outside air is, for example, approximately equal to a volume concentration of the second vapor mass.

The outlet 12 may generally be provided, for example, with a non-return valve. This can largely prevent outside air being drawn in when as a result of condensation a reduced pressure arises in the vapor buffer space and/or in the condenser 4. In the example of FIG. 1, the outlet 12 is situated lower than an upper side 14 of the heat buffer body 5.

More generally, the vapor buffer space is preferably closed by the casing 10 at an upper side 15 of the vapor buffer space. This allows the vapor collected in the vapor buffer space 8 to be collected as a result of density differences with respect to the outside air. By an open communication of the vapor buffer space 8 with the outside air, for example, via the outlet 12, it can be achieved that the pressure in the vapor buffer space 5 and in condenser 4 are substantially approximately atmospheric.

In the first embodiment, the supply 6 is connected to the condenser 4 near an underside 16 of the heat buffer body 5. The condenser can also be provided with a discharge 18 for discharging the condensed vapor from the heat buffer body 5. In general, the condenser 4 can be provided with a housing 20. At the supply 6 and/or the discharge 18 the housing 20 can be provided with a supply opening 6′ and/or a discharge opening 18′, respectively. This enables supply of the vapor and discharge of the condensed vapor, respectively. The housing 20 can also be provided, preferably at an upper side thereof, with a buffer opening 22. With this, the fluid communication with the heat buffer body 5 can be effected.

Preferably, the apparatus is provided with a coolant supply 24. From the coolant supply 24 the coolant, in use, can flow, for example downwardly, over the heat buffer body 5. By means of the coolant supply 24, the coolant, for example, water possibly having additives added thereto, can flow over a surface of the heat buffer body 5. As a result, in use, the heat buffer body 5 can be cooled. In the example of FIG. 1, the discharge 18 is also designed for discharging the coolant.

The apparatus 2 can, in a variant of the first embodiment, be provided with a process space 30. The apparatus can be designed for discharging the coolant to the process space 30 for heating the process space 30. Such discharge can be effected, for example, with a pump, and/or by gravity.

Preferably, more generally, the coolant supply 24 is connected to the process space 30. This makes it possible for coolant to be recycled from the process space 30 back to the condenser 4. Accordingly, the coolant can be reused in the condenser 4. Thus, the apparatus 2 can be provided with a closed coolant circuit. This allows saving on coolant.

In the above-mentioned, or in another, embodiment of the first embodiment, the apparatus 2 can be provided with the process vessel 3. The process vessel 3 can be designed for carrying out a process under pressure, such as the steam peeling process, wherein under the influence of the pressure intermittently a vapor charge is released during an opening time of the process vessel. Preferably, the heat capacity of the heat buffer body 5 is chosen to be so small that, in use, supply of the vapor charge to the heat body 5 leads to condensation of only a part, for example, the first part, of the vapor charge during a time interval equal to the opening time. It will be clear to the skilled person how large the heat capacity of the heat buffer body needs to be chosen to accomplish that initially only the first part of the vapor charge condenses during the time interval equal to the opening time. In general, the opening time is typically in a range of 1 to 3 seconds.

A volume of the vapor buffer space can be defined as the volume of the vapor buffer space in which vapor can be stored. The volume of the vapor buffer space can be greater, in particular five times greater, more particularly ten times greater, for example, fifteen times greater, than a volume of the process vessel 3. This allows expansion of the charges of vapor, for example, from a situation in the process vessel 3 in which the charges of vapor may be under pressure to a situation in the vapor buffer space 8 in which the charges of vapor can have approximately an atmospheric pressure. The volume of the process vessel can then be defined, for example, as the volume which, in use, is placed under pressure, and from which intermittently vapor, in particular steam, can be released.

FIG. 2 shows a cross section of the condenser 4 of the apparatus 2 according to the first embodiment and variants thereof. FIG. 2 shows the heat buffer body 5. The heat buffer body 5 comprises in this example a package 25 with a plurality of smooth plates 31. The condenser can, at least partly, be formed by the surface 32 of the smooth plates. More generally, the plates can be set up vertically. This renders the flat plates suitable in particular for supply of the second part of the vapor charge downwardly from the vapor buffer space 8 to the heat buffer body 5, and/or for transport of vapor charges upwardly through the condenser 4. The condenser 4 can also comprise the housing 20.

The smooth plates 31 are set up together with mutual interspaces. The flat plates can touch each other, for example, by their edges. In other examples, flat plates can be set up completely free of each other. Preferably, the plates are made substantially of a metal, for example, steel. Steel is a material that contributes to a relatively high heat capacity of the heat buffer body. The sheet form can contribute to a relatively fast heat exchange between the vapor and the heat buffer body. The heat buffer body can also be designed differently, for example, using ceramic elements.

FIG. 3 shows a schematic representation of an apparatus 2 for condensing charges of vapor in a second embodiment according to the invention. FIG. 3 shows the condenser 4, the heat buffer body 5, and the supply 6. FIG. 3 further shows the vapor buffer space 8 bounded by the casing 10. The casing 10 is provided with the outlet 12 for gas discharge to the environment 34 of the casing 10, for example, to the outside air. In FIG. 3 the outlet 12 is situated near an underside 13 of the vapor buffer space 8. In the example of FIG. 3 the outlet 12 of the vapor buffer space is provided with a gas discharge conduit 36. The gas discharge conduit 36 can also be used in other examples. Using the gas discharge conduit 36, a location where the discharged gas reaches the environment 34 of the casing 34 can be influenced.

FIG. 4 shows a schematic representation of an apparatus 2 in a third embodiment according to the invention. FIG. 4 shows the condenser 4, the heat buffer body 5, and the supply 6. FIG. 4 further shows the vapor buffer space 8 bounded by the casing 10.

In the third embodiment, the vapor buffer space comprises a first vapor buffer space chamber 8A and a second vapor buffer space chamber 8B. The first vapor buffer space chamber 8A and the second vapor buffer space chamber 8B are mutually connected by a vapor buffer space conduit 8C. By means of the vapor buffer space conduit 8C and the second vapor buffer space chamber 8B, the second part of the vapor charge can be collected at a position remote from the condenser. This enhances a flexibility in the placement of the apparatus 2. The reason for this is that the volume of the vapor buffer space can be relatively large, so that in some situations there may not be sufficient space available for placing the vapor buffer space 8 near the condenser 4. Besides being used in the third embodiment, the vapor buffer space 8 comprising the first vapor buffer space chamber 8A, the second vapor buffer space chamber 8B, and the vapor buffer space conduit 8C interconnecting the first vapor buffer space chamber 8A and the second vapor buffer space chamber 8B, may be used more generally in the apparatus 2.

In the example of FIG. 4, the casing 10 is further provided with the outlet 12 for gas discharge to the environment 34 of the casing 10. In FIG. 4 the outlet 12 is situated near an underside 13 of the vapor buffer space 8. The outlet 12 can be arranged, for example, in the second vapor buffer space chamber 8B.

Using the apparatus 2 in the first, second, and/or third embodiment, intermittently released vapor charges, also referred to as vapor emissions, can be conducted from the underside 16 upwards through the heat buffer body 5 and initially be condensed only partly. The non-condensed part of a vapor charge conducted through the heat buffer body 5 can be temporarily collected in the vapor buffer space 8. Such not yet condensed vapor emission can be condensed at a later stage, after being supplied to the heat buffer body 5. Such supply can be effected, for example, in that, as a result of condensation of vapor already present in the vapor buffer space 8, a sucking action is created. As the vapor collected in the vapor buffer space 8, after being supplied to the heat buffer body 5, can condense on the heat buffer body 5, the sucking action can continue until the vapor buffer space is substantially free of vapor and filled with residual gas.

A first embodiment of a method according to the invention (the first method) can be carried out with the aid of, for example, the apparatus 2 in the first, second, or third embodiment. The first method comprises the condensing on the heat buffer body 5 in the condenser 4 of condensable components of charges of vapor, in particular water vapor, more particularly steam, intermittently released from the process vessel 3. While a part of a vapor charge is supplied directly to the heat buffer body 5, another, second part of the vapor charge is first supplied to the vapor buffer space. Thereupon, in the first method, the other, second part of the vapor charge is supplied to the heat buffer body 5 only after at least partial condensing of the first part of the vapor charge.

The process vessel can be used for peeling tuberous crops, in particular potatoes, by means of a steam peeling process, which steam peeling process comprises intermittently releasing steam charges from the process vessel. Condensing can be carried out with the aid of the condenser 4 provided with the heat buffer body 5. The first method comprises transporting the first part of a vapor charge to the heat buffer body 5, followed by condensing the first part of the vapor charge on the heat buffer body 5. The first method further comprises transporting the second part of the vapor charge to a vapor buffer space 8 bounded by the casing 10, followed by collecting the second part of the vapor charge in the vapor buffer space 8 during and possibly after, at least partial, condensing of the first part of the vapor charge on the heat buffer body 5. The first method furthermore comprises, after supplying the second part of the vapor charge from the vapor buffer space 8 to the heat buffer body 5, condensing the second part of the vapor charge on the heat buffer body 5 after at least partial condensing of the first part of the vapor charge on the heat buffer body 5.

FIG. 5 shows a graph in which a weight of vapor masses, in this example steam masses, M (in kilograms) is shown as a function of time T (in seconds). With the aid of FIG. 5 a variant of the first method can be illustrated, which can be carried out with the aid of the apparatus 2 in the first embodiment. This variant comprises transporting the second part of the vapor charge via the heat buffer body 5 to the vapor buffer space 8. So, the first and second part of the vapor charge can be supplied to the heat buffer body as a single vapor charge. The first part of the vapor charge can be distinguished from the second part of the vapor charge in that the first part of the vapor charge condenses on the heat buffer body 5 directly, i.e., without first reaching the vapor buffer space 8, after transporting to the heat buffer body 5. The second part of the vapor charge, by contrast, can shoot through the condenser 4 on to the vapor buffer space 8, thence to be supplied, later, to the condenser 4 again.

The variant of the first method comprises peeling of, for example, potatoes by means of a steam peeling process which comprises intermittently releasing steam from the process vessel. The process vessel is then designed, for example, for peeling potatoes by means of a steam peeling process which comprises intermittently releasing steam from the process vessel.

FIG. 5 illustrates the manner in which, in the variant of the first method, released steam from the process vessel 3 can be collected in the vapor buffer space 8, can be condensed in the condenser 4, and can be discharged with the aid of the coolant. FIG. 5 shows four different lines indicated with L₁, L₂, L₃, and L₄. Line L₁ represents a first steam mass which has been cumulatively released from the process vessel during a process period. Line L₂ represents a second steam mass, to be buffered in the condenser 4. The second steam mass indicated with line L₂ is equal to the first steam mass (line L₁) cumulatively released from the process vessel, reduced by a third steam mass which has meanwhile condensed and which can have been discharged by the coolant via the discharge 18. Line L₃ represents the third steam mass whose heat is momentarily stored in the heat buffer body 5. The third steam mass, accordingly, has condensed on the heat buffer body. Line L₂ and line L₃ in this example coincide in the process period after time T_(p) has been reached. A fourth steam mass, which, in the variant of the first method, shoots through the thermal buffer, is stored in the vapor buffer space 8, until the heat buffer body 5 has been cooled by the coolant such that it can take up and condense steam from the vapor buffer space 8 again The fourth steam mass stored in the vapor buffer space 8 (in the form of steam) is accordingly represented in this example by the line L₄. It will thus be clear that, in this example, at time T_(p) the vapor buffer space 8 is substantially empty.

In the example thus described, the second part of the vapor charge can be formed, for example, by the fourth steam mass, since this is the steam mass initially shooting through the condenser 4 without condensing directly. The first part of the vapor charge can be formed, for example, by the third steam mass. For it appears from FIG. 5 that the fourth vapor mass is collected in the vapor buffer space during and possibly after the at least partial condensing of the third steam mass on the heat buffer body. It will also be clear that as a result of collection of the fourth steam mass in the buffer space, a period in which the vapor charge is supplied to the heat buffer body can be prolonged. A heat capacitating ability of the heat buffer body can be lowered. This appears, for example, from a platform 40 which is formed by the third line L₃. This platform is determined inter alia by a magnitude of the heat buffer body 5. The magnitude of the heat buffer body 5 co-determines the condensing ability of the heat buffer body 5. So, if the heat buffer body is relatively small, the platform 40 will be located relatively low. If the vapor is formed by steam, the heat buffer body, during the time that line L₃ is on the platform, can have a temperature of about 100° C.

So, the mass of heat buffer body 5 can be limited because only a part of the supplied vapor charge is to be initially condensed. The remaining part can, in use, be stored in the volume buffer and can be condensed later, while the heat buffer body 5 can be cooled by the coolant.

FIG. 5 shows two process periods in which steam is released from the process vessel 3. In the example of FIG. 5 each process period lasts about 60 seconds. So, a frequency of the intermittent release of the vapor charges in this example is about 1/60 Hertz. It will be clear that the steps that are carried out during the process period can be repeated more than once. Preferably, the steps are repeated during a plurality of uninterrupted process periods. The opening time of the process vessel for releasing the vapor charge in this example is about 2 seconds. The first steam mass in this example is about 19 kilograms. Preferably, in this example, the volume of the first and the second part of the vapor charge, the flow rate of the coolant flow, and a heat capacity of the heat buffer body have been so chosen for controlling the temperature of the coolant in a range of from 70 to 100 degrees Celsius.

A second embodiment of a method according to the invention (the second method) comprises, in addition to the steps of the first method, downwardly supplying the second part of the vapor charge from the vapor buffer space 8 to the heat buffer body 5. The second method can further comprise, during collection of the second part of the vapor charge in the vapor buffer space 8, discharging residual gas from the vapor buffer space 8, via the outlet 12 situated near the underside 13 of the vapor buffer space 8. The second method can further comprise transporting the first part of the vapor charge through the supply 6 of the condenser 4 to the heat buffer body 5. At least the first part of the vapor charge can then be conducted substantially upwards through the heat buffer body 5, for example, via the supply situated near the underside 16 of the heat buffer body 5.

Preferably, the second method further comprises discharging the condensed vapor from the heat buffer body 5. This can comprise, for example, cooling the heat buffer body 5 by means of a coolant flow over the surface 32 of the heat buffer body. Cooling is preferably carried out during condensing of the first and the second part of the vapor charge. Preferably, cooling is further carried out following condensing of the first and the second part of the vapor charge. Typically, a continuous, for example, uninterrupted, coolant flow along the surface 32 of the heat buffer body 5 takes place.

The second method further comprises discharging the coolant to the process space 30 which is designed for carrying out a heat requiring process.

It will thus be clear that, in an embodiment such as the first method and/or the second method, the vapor charge can be conducted to the heat buffer body 5 on which the vapor charge condenses partly. The non-condensed, remaining vapor, which after passage through the heat buffer body 5 leaves this heat buffer body 5 again, can be collected in the vapor buffer space 8 which is directly connected to the heat buffer body 5. The collected vapor can still be condensed on the heat buffer body 5 later, as a result of a sucking action (by volume decrease) of condensing vapor already present in the heat buffer body 5.

The heat that has been released by condensation of vapor on the heat buffer body 5 can be temporarily collected in the heat buffer body 5. This can be accompanied by a temperature increase of the heat buffer body 5. The stored heat can be gradually removed by continuously irrigating the heat buffer body 5 with the coolant. The heated coolant can leave the heat buffer body and be discharged simultaneously with the condensed vapor through the discharge 18.

The inventors thus realized that, with one or more of the embodiments described, by proper dimensioning of the heat buffer body 5 and of the volume of the vapor buffer space 8, it is possible to condense the released vapor charges in an efficient manner, with a relatively high temperature of a coolant flow leaving the heat buffer body 5. The absorption potential of the heat buffer body 5 accordingly can be chosen relatively small, because in the vapor buffer space 8 non-condensed vapor can be temporarily collected. A time duration of the thermal loading by condensation can therefore be longer than the opening time of the process vessel, i.e., a time duration of the release of a single vapor charge.

An important idea behind the invention is therefore that the second part of the vapor charge does not condense directly on the heat buffer body but is first collected in the vapor buffer space before being supplied to the heat buffer body to condense thereon. Transport of the second part of the vapor charge for supply to the heat buffer body to condense thereon can proceed via a different path than transport of the first part of the vapor charge. With the aid of the invention, condensing of the vapor charge can therefore take place in a manner more spread in time, through the delayed supply of the second part of the vapor charge to the heat buffer body.

In summary, described herein is a method for condensing on a heat buffer body in a condenser condensable components of charges of vapor intermittently released from a process vessel, wherein, while a part of a vapor charge is supplied directly to the heat buffer body for condensation, another part of the vapor charge is first supplied to a vapor buffer space for buffering, and wherein the other part of the vapor charge is supplied to the heat buffer body only after at least partial condensing of the first part of the vapor charge. Also described herein is an apparatus for condensing on a heat buffer body in a condenser condensable components of charges of vapor intermittently released from a process vessel.

It is noted that the invention is not limited to the exemplary embodiments represented here, but that many variations are possible. Thus, for example, the second part of the vapor charge may be conducted to an additional condenser. Thus the vapor charge may be transported to a plurality of, for example, parallel running, condensers. Such variations will be clear to the skilled person, and are understood to be within the scope of the invention as set forth in the following claims. 

1. A method for condensing on a heat buffer body in a condenser housing condensable components of charges of vapor intermittently released from a process vessel, the method comprising: transporting a first part of a vapor charge directly to the heat buffer body for condensation thereon, transporting a second part of the vapor charge to a vapor buffer space for volume buffering, providing fluid communication between the condenser housing and the vapor buffer space and transporting the second part of the vapor charge downwardly from the vapor buffer space to the heat buffer body only after at least partial condensing of the first part of the vapor charge.
 2. (canceled)
 3. The method according to claim 1, wherein the vapor charge is steam, and wherein the pressure in the condenser housing and in the vapor buffer space is substantially atmospheric.
 4. The method according to claim 1, wherein the vapor buffer space is in open communication with the ambient air.
 5. The method according to claim 4, which comprises on the basis of mass density difference, keeping the second part of the vapor charge of relatively low mass density and ambient air of relatively high mass density substantially separate. 6-9. (canceled)
 10. The method according to claim 1, which comprises, during collecting of the second part of the vapor charge in the vapor buffer space, discharging residual gas from the vapor buffer space, via an outlet situated near an underside of the vapor buffer space.
 11. The method according to claim 1, wherein the second part of the vapor charge is transported to the vapor buffer space via the condenser housing and the heat buffer body contained therein.
 12. (canceled)
 13. The method according to claim 1, wherein at least the first part of the vapor charge is conducted upwardly through the condenser housing and the heat buffer body contained therein.
 14. (canceled)
 15. The method according to claim 1, which also comprises discharging the condensed vapor from the heat buffer body.
 16. The method according to claim 1, which also comprises cooling the heat buffer body by means of a coolant flow over a surface of the heat buffer body. 17-18. (canceled)
 19. The method according to claim 16, which comprises discharging the coolant to a process space, which process space is designed for carrying out a heat requiring process.
 20. The method according to claim 16, wherein a frequency of intermittently releasing the vapor charges, an opening time of the process vessel for releasing the vapor charge, a volume of the first and the second part of the vapor charge, a flow rate of the coolant flow, and a heat capacity of the heat buffer body are chosen for controlling the temperature of the coolant in a range of from 70 to 100 degrees Celsius.
 21. The method according to claim 1, which comprises peeling tuberous crops, in particular potatoes, in the process vessel by means of a steam peeling process, which steam peeling process comprises intermittently releasing steam charges from the process vessel.
 22. An apparatus for condensing condensable components of charges of vapor intermittently released from a process vessel, the apparatus comprising: a condenser housing provided with a heat buffer body disposed therein for condensing on the heat buffer body the condensable components of the released vapor charges; a supply for transporting therethrough the released vapor charges from the process vessel to the heat buffer body; a vapor buffer space bounded by a casing, at least partly above the heat buffer body, which is configured for, while a first part of a released vapor charge is condensing in the condenser, therein collecting a second part of the vapor charge, the vapor buffer space in fluid communication with the condenser and the heat buffer body disposed therein for supplying the second part of the vapor charge downwardly to the heat buffer body after the first part of the vapor charge has at least partly condensed thereon.
 23. The apparatus according to claim 22, wherein the casing is provided with an outlet for gas discharge to an environment outside of the casing, and wherein the vapor buffer space is in open communication with the ambient air.
 24. The apparatus according to claim 23, wherein the outlet is placed for lower than a downstream side of the heat buffer body. 25-27. (canceled)
 28. The apparatus according claim 22, wherein the casing is in fluid communication with the supply via the condenser housing and the heat buffer body contained therein.
 29. The apparatus according to claim 22, wherein the supply is connected to the condenser housing near an underside of the heat buffer body.
 30. The apparatus according to claim 22, wherein the condenser housing is provided with a discharge for discharging the condensed vapor from the heat buffer body.
 31. The apparatus according to claim 22, further comprising a coolant supply for cooling the heat buffer body by providing a coolant flow over a surface of the heat buffer body.
 32. The apparatus according to claim 31, wherein the condenser housing is provided with a discharge for discharging the condensed vapor from the heat buffer body and wherein the discharge is further designed for discharging the coolant.
 33. The apparatus according to claim 32, further comprising a process space, wherein the apparatus is configured to discharge the coolant to the process space for heating the process space.
 34. The apparatus according to claim 22, wherein the heat buffer body comprises a package with a plurality of smooth plates which are set up together with mutual interspaces.
 35. The apparatus according to claim 34, wherein the plates are made substantially of steel.
 36. (canceled)
 37. The apparatus according to claim 22 further comprising the process vessel.
 38. The apparatus according to claim 37, wherein the process vessel is configured to carry out a process under pressure, wherein under the influence of the pressure intermittently a vapor charge is released during an opening time of the process vessel, wherein a heat capacity of the heat buffer body is chosen so small that, in use, supply of the vapor charge to the heat buffer body leads to condensation of only a part of the vapor charge during a time interval equal to the opening time.
 39. The apparatus according to claim 37, wherein a volume of the vapor buffer space is greater than a volume of the process vessel.
 40. The apparatus according to claim 37, wherein the process vessel is designed for peeling at least one of vegetables, fruit, tuberous crops by means of a steam peeling process which comprises intermittently releasing steam from the process vessel.
 41. The apparatus according to claim 23, wherein the outlet is provided with a non-return valve. 